Supporting the Gut-Brain Axis Through Nutritional Supplementation

December 21, 2017

In recent years, researchers have been uncovering relationships between body systems that were previously believed to be only peripherally connected. One such relationship is the gut-brain axis, which refers to the constant and bidirectional communication between the central nervous system and the components of the enteric nervous system that are located in the gut.

Within the brain, there are both emotional and cognitive centers that are closely tied to gastrointestinal function, and these interactions are mediated by gut microbiota. Disruptions in the gut-brain axis that can cause debilitating symptoms are associated with a wide range of health conditions ranging from autism to anxiety to irritable bowel syndrome. Depending on the patient and the condition, these symptoms can include constipation, diarrhea, anxiety, and mood swings. For disorders like irritable bowel syndrome, gut-brain axis disruptions may be causative, while for conditions like autism, they can exacerbate the symptoms that already characterize the patient’s condition. Thus, optimizing the functioning of the gut-brain axis can aid in the support and maintenance of both physical and mental wellness.

There are several different types of nutritional supplements that can facilitate the functioning of the gut-brain axis by supporting the health of the gut microbiome. Probiotic, prebiotic, and vitamin B12 supplements can all have positive impacts on the microbial community in the gut, which can help alleviate the symptoms of the many intestinal, neurological, and psychiatric disorders that have been tied to the gut-brain axis. These supplements can also play a critical role in increasing the absorption of bioavailable nutritional supplements that have been shown to reduce symptoms related to the gut-brain axis.

The Potential for Probiotics and Prebiotics to Enhance the Gut Microbiome

The bulk of the research on nutritional supplements that support the health of the gut-brain axis focuses on the benefits of probiotic supplements. A probiotic supplement directly introduces “good bacteria” into the gut microbiome. These bacteria can enhance the function of the gut in many different ways, such as increasing nutrient absorption and improving gut motility. Alongside these benefits, a healthy gut microbiome also contributes to the development of strong communication links between the brain and the gut. As a result, studies indicate that taking a probiotic supplement can help with a wide range of gut- and brain-related health conditions, including intestinal inflammation, gut motility, stress, anxiety, and depression.

While probiotic supplements support the health of the gut microbiome by directly adding “good” bacteria to the gut, prebiotic bacteria provide a different benefit. Prebiotics are short-chain carbohydrates that are derived from plant fibers. Depending on their chemical structures, they fall into two categories: fructo-oligosaccharides (FOS) or galacto-oligosaccharides (GOS). These carbohydrates are not digestible. Rather, they serve as a food source for the good bacteria in the gut, enabling them to grow and proliferate. Thus, taking a prebiotic supplement results in the maintenance of a healthy gut microbiome that is well-positioned to optimize the signaling that makes up the gut-brain axis.

Vitamin B12 Supplement May Support the Health of the Gut Microbiome

New research also suggests that vitamin B12 (cobalamin) may help support the gut-brain axis by modulating the ecology of the gut microbiome. Researchers have found that vitamin B12 plays a key role in multiple biological processes in gut bacteria that support the gut-brain axis. For instance, vitamin B12 may be involved in enzymatic reactions in the metabolic and DNA synthesis pathways in bacteria. However, humans do not naturally produce enough vitamin B12 for gut bacteria to take advantage of the nutrient. Thus, taking a supplement will introduce the nutrient into the gut, where its abundance is otherwise relatively low, and enable bacteria to utilize the nutrient to optimize their function—and, in turn, the signaling of the gut-brain axis.

There is a wide range of nutrients that may be able to aid in the treatment of the intestinal, neurological, and psychiatric disorders that are associated with the gut-brain axis. For example, research suggests that taking supplements of vitamin C, zinc, magnesium, folic acid, and omega-3 fatty acids in bioavailable forms may help protect against depression and anxiety and alleviate a range of symptoms linked to the gut-brain axis. There is also emerging evidence that bioavailable forms of cyanocobalamin and levocarnitine may reduce the severity of autism symptoms.

The effectiveness of these supplements for alleviating symptoms may be explained by the fact that a healthy gut microbiome helps boost the absorption of nutrients when they are taken in bioavailable forms. In contrast, a suboptimal gut microbiome can block the uptake of nutrients in the gut. This serves as yet another indicator of the importance of introducing good bacteria into the gut with probiotic supplements and stimulating their function by taking prebiotic supplements and vitamin B12. These strategies can help patients make the most of the other bioavailable supplements that they take for symptoms that are related to the gut-brain axis.

Overall, when it comes to providing nutritional support for the gut-brain axis, keeping the microbiome healthy is paramount. With probiotics, prebiotics, and vitamin B12 supplements, it is possible to directly support the microbial communities that facilitate the functioning of the gut-brain axis. Taking these supplements can improve the bioavailability of supplements that may alleviate symptoms of diseases and disorders that are commonly associated with the gut-brain axis.

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